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This paper reports on a research study that focused on predicting the loss of construction workers’ productivity due to thermal environment variations. The paper utilises a statistical polynomial regression analysis to establish a relationship between productivity and the predicted mean vote (PMV) thermal comfort index. In doing so, it builds upon a substantial amount of data reported in the literature regarding construction productivity and thermal environment. A set of equations reflecting the nature of the construction task being performed as well as the thermal environment are proposed to predict the degree of change in workers’ productivity, according to a change in the thermal environment. The paper also reports on an experimental investigation undertaken to validate the developed equations. Validation results indicate that the developed equations can predict productivity with a reasonable level of accuracy. Furthermore, they show that the workers’ productivity decreases as the PMV index moves away from the optimum range for all the observed tasks.

This paper aims to measure the thermal comfort conditions and indoor air quality parameters, through on-site measurements taken in the areas mostly occupied by the passengers and airport staff. Terminal buildings consist of areas with various functions. Heating, ventilation and air conditioning requirements vary from area to area, thus leading to challenges in the management of indoor environment quality. Therefore, the study focuses on investigating the indoor environment conditions in various areas of the terminal buildings.

In this study, the thermal comfort and indoor air quality were evaluated based on the parameters [CO₂ concentration, relative humidity, temperature, predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD)] collected for summer 2019 from different zones inside the International Dalaman Airport terminal building located in the southwest of Turkey. The measurements were performed in the areas mostly occupied by the airport staff and passengers (check-in area, security control areas, international departure lounge, domestic departure lounge and baggage claim hall).

As a result of the study, it was observed that the CO₂ concentration was 480–965 ppm, the relative humidity was 51.9–75.8% and the temperature was in the range of 23.9°C–28.3°C inside the airport terminal. The PMV values were determined to be in the range of −0.23 to 0.67, and the PPD values 5–15%, which are used to measure the thermal comfort conditions.

There has been limited study on the determination of the indoor air quality in airport terminals and the investigation of the thermal comfort conditions. However, in this study, indoor air quality and thermal comfort conditions were determined by on-site measurements in the five mostly occupied areas by passengers and employees in the terminal building.

Recent studies have found that the high demand for air-conditioning usage in tropical countries has affected the thermal adaptability of building occupants to hot weather, and increased building energy consumption. This pilot study aims to investigate the effects of transient thermal environment changes on participants' sensory and physiological responses.

The change of thermal perceptions, skin temperatures and core temperatures when exposed to transient thermal environments (cool-warm-cool) from 10 college-aged female participants during a simulated daily commute by foot to class in a tropical university campus were investigated. Subjective measurements were collected in real-time every 5 min.

The main finding suggests that participants were acclimatised to cool air-conditioned indoor environments, despite exhibiting significant mean skin temperature differences (p < 0.05). In addition, exposure to uniform air conditioning from 17 to 18°C for 20 min was thermally unacceptable and reduced concentration during given tasks.

The study focused on thermal comfort conditions in a uniform air-conditioned lecture hall, and the findings may not be applicable for residential and other private building spaces. The distinct temperature difference between indoor and outdoor in the tropical built environment resulted in high dependence on air-conditioning usage. The building occupants' well-being and energy conservation implications of the findings are discussed.

This study provides the platform for discussion on the dynamics of occupants' comfort level and adopting a more variable thermal environment in tropical spatial transient thermal environments among architects and building management system managers. The findings from this study may contribute to the Malaysian Standards for Energy Efficiency and Use of Renewable Energy for Non-Residential Buildings (MS1525).

A knowledge gap in adaptive thermal comfort due to exposure from transient conditions in tropical university campus for energy efficiency revision has been investigated.

University students’ lecture theatre concentration levels are significantly related to indoor environmental quality (IEQ). The purpose of this study is to investigate the relationship between indoor environmental quality (IEQ) and the self-reported concentration levels of university students during the winter at University College London (UCL), UK.

A questionnaire survey and physical measurements were used to assess the IEQ factors affecting students’ concentration levels.

The lecture theatre design factor was the most significant factor influencing students’ concentration levels, and the facility environment was more important than the thermal environment, indoor air quality, and acoustic environment in influencing students’ concentration levels in this winter investigation at UCL, UK. Additionally, students prefer a colder thermal environment. The concentration level of students was positively correlated with the indoor air quality and negatively correlated with the acoustic environment.

Based on model application, this research could provide lecture theatre IEQ design. This research additionally provides an acceptable indoor thermal environment temperature range based on a large sample, which can be used to calibrate a student performance benchmark.

As this study evaluates the IEQ factors that influence the concentration levels of university students, interior designers and engineers should consider the rational layout of these factors. Therefore, this study may provide a reference for the interior environmental design of lecture theatres in educational buildings.

Sleep is a vital and a basic activity of human life and it is a physiological need for human body. Sleep quality is directly influenced by the comfort conditions of sleep environment. The purpose of this paper is to define the role of textile materials utilized as bed fabrics on air and mass transfer from the human body.

Thermal conductivity, thermal resistance, thickness, water vapour permeability and air permeability properties of fabrics were analyzed and statistically evaluated. Thermal conductivity and resistance measurements were performed in Alambeta test instrument. Water vapour permeability tests were done according to the Rotating Platform method, and air permeability was measured in FX 3300 Textest air permeability tester. Relationships between comfort parameters were statistically evaluated with correlation analysis.

Comfort is a major concept in the determination of overall life quality as well as sleep quality of a resting person. Therefore academic studies about thermal comfort prediction of sleep environment and bed surface fabrics are of great importance. This study investigates conventional mattress ticking fabrics in terms of comfort parameters and defines the important fabric properties on comfort parameters.

Sleep comfort is a promising area in textile comfort studies with its dynamics different from body thermal comfort during daily life. However, in general comfort studies are about garment materials which are in direct contact with the skin. This study tries to define the comfort status of textile materials which have indirect contact with the human body surface during sleep duration.

The purpose of this paper is to analyse thermal comfort and the thermal environment in naturally ventilated classrooms. Specifically, the aims of the study were to identify the thermal environment and thermal comfort of respondents in naturally ventilated university classrooms and compare them with the ASHRAE and Indonesian National Standard (SNI); to check on whether the predicted mean vote (PMV) model is applicable or not for predicting the thermal comfort of occupants in naturally ventilated university classrooms; and to analyse the neutral temperature of occupants in the naturally ventilated university classrooms.

The study was carried out at the new campus of Faculty of Engineering, Hasanuddin University, Gowa campus. A number of field surveys, which measured thermal environments, namely, air temperature, mean radiant temperature (MRT), relative humidity, and air velocity, were carried out. The personal activity and clothing properties were also recorded. At the same time, respondents were asked to fill a questionnaire to obtain their thermal sensation votes (TSV) and thermal comfort votes (TCV), thermal preference, and thermal acceptance. A total of 118 respondents participated in the study. Before the survey was conducted, a brief explanation was provided to the participants to ensure that they understood the study objectives and also how to fill in the questionnaires.

The results indicated that the surveyed classrooms had higher thermal environments than those specified in the well-known ASHRAE standard and Indonesian National Standard (SNI). However, this condition did not make respondents feel uncomfortable because a large proportion of respondents voted within the comfort zone (+1, 0, and −1). The predictive mean vote using the PMV model was higher than the respondents’ votes either by TSV or by TCV. There was a huge difference between neutral temperature using operative temperature (T_o) and air temperature (T_a). This difference may have been because of the small value of MRT recorded in the measured classrooms.

The research shows that the use of the PMV model in predicting thermal comfort in the tropic region might be misleading. This is because PMV mostly overestimates the TSV and TCV of the respondents. People in the tropic region are more tolerant to a higher temperature. On the basis of this finding, there is a need to develop a new thermal comfort model for university classrooms that is particularly optimal for this tropical area.

As climate change disproportionately affects vulnerable populations, ensuring thermal comfort for older adults is magnified in tropical senior living environments. This study explores the lived experiences of older adults' thermal comfort in senior living facilities in a tropical climate and how these experiences impact their overall well-being.

Employing Moustakas' transcendental phenomenology and the Modified Stevick-Colaizzi-Keen method, this study investigated older adults' thermal experiences through semi-structured interviews with 28 participants in six urban senior living facilities in Malaysia.

Four primary themes emerged: fabric and function; atmospheric conditions and living dynamics; thermal dynamics and environmental comfort; temperature tensions of stress, sound, and sensitivity. Our findings underscore the importance of considering the multisensory and multi-faceted nature of thermal comfort for older adults, considering sensory aspects, early life experiences, cultural practices, and personal preferences, particularly in tropical climates.

As one of the first to explore the thermal comfort of older adults in senior-friendly accommodations in a tropical climate, the findings provide a comprehensive understanding of older adults' diverse thermal comfort needs and offer practical recommendations for environments that support healthy aging. By integrating insights from hospitality, gerontology, and environmental studies, this research contributes to the promotion of public health and aligns with global objectives to improve the well-being of the aging population.

The paper aims to determine the thermal comfort perception of schoolchildren from a warm and humid environment. There is a concern about the effect of high temperature on the health and academic performance of schoolchildren.

Objective and subjective methodological approaches were adopted to collect data during the fieldwork in the selected primary schools. ASHRAE adaptive comfort model was adopted to analyze the data.

The paper provided empirical results about the comfort requirements of schoolchildren from the warm and humid environment. During the occupied school time, the studied schoolchildren were found to tolerate temperatures higher than the upper limit temperature recommended by ASHRAE Standard 55. The paper recommends that the studied children may not need any active ventilator to be thermally comfortable during the occupied school hours

The paper found the range of temperatures that schoolchildren from the warm and humid environment can adapt to. The information may be useful to architects, engineers and facility managers

As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation.

Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices.

Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient.

This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions.

This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment.

There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey.

First, the contributions of spatial characteristics to microclimate were analyzed. And the results from mobile measurements were compared to those from fixed measurements to examine accuracy of mobile method. Air temperature and physiologically equivalent temperature (PET) profiles were plotted to explore the impacts of the spatial characteristics of that urban square and local street.

This research investigates the effects of urban canyons and landscape on air temperature and outdoor thermal comfort in an open square in Seoul, Korea, a city of diverse thermal environments. Mobile field measurements were carried out to obtain local meteorological data based on higher spatial resolution.

On a day in October under clear sky, air temperature and PET differences of up to 1.77 °C and 9.6 °C were observed at 2 p.m. and 3 p.m., respectively. These were mainly from the impact of shading effects caused by surrounding obstacles. The current layout and volume of vegetation in the square seemed not effective for reducing air temperature and improving thermal comfort, which needs further study.

The authors tested a way to investigate time delay when using mobile measurements by correcting measured local data using adjacent meteorological observatory data. The findings of and limitations on mobile station-based field measurement and analysis are discussed herein.